python39Packages.chameleon: propagate importlib-metadata

pkgs/development/python-modules/chameleon/default.nix

@@ -2,7 +2,9 @@
 , buildPythonPackage
 , fetchFromGitHub
 , setuptools
+, importlib-metadata
 , pytestCheckHook
+, pythonOlder
 }:
 
 buildPythonPackage rec {
@@ -21,6 +23,10 @@ buildPythonPackage rec {
     setuptools
   ];
 
+  dependencies = lib.optionals (pythonOlder "3.10") [
+    importlib-metadata
+  ];
+
   nativeCheckInputs = [
     pytestCheckHook
   ];